Chemotherapy is an infusion of anti-tumor drugs into the patient’s body, which will reach all organs of the body through blood vessels and have a killing effect on tumors in all areas. This is very different from radiotherapy, which is a radiation treatment for tumors in a certain area and has a limited treatment scope and can only control the tumors in the irradiated area. Chemotherapy is an important tool in tumor treatment. For most patients with early stage tumors, chemotherapy is required after surgery to kill any tumor cells that may remain in the body. Some patients with early-stage tumors also need chemotherapy before surgery to reduce the size of the tumor so that the surgical resection will be more complete and thus achieve the best treatment effect. For patients with recurrence after surgery or inoperable once found, chemotherapy is even more important. This is because patients often have multiple organ or tissue tumor metastases at this time. In this case, chemotherapy is usually administered first to control the tumor in various parts of the body and prevent its further development. Patients with different types of tumors are treated with different chemotherapy drugs, for example, a combination of two drugs is often used to treat lung cancer: paclitaxel, doxorubicin, gemcitabine, one of vincristine in combination with platinum-based agents. In contrast, the commonly used chemotherapeutic agent for patients with bowel cancer is fluorouracil in combination with platinum oxalate or irinotecan. For breast cancer, there are relatively more types and combinations of chemotherapeutic agents to choose from. Because the types of drugs used are different, the way of using them is also different. For example, high-dose cisplatin infusion requires more fluids and a diuretic. This is because cisplatin has toxic effects on the kidneys, and large amounts of fluids and urination are needed to facilitate the elimination of cisplatin from the body as soon as possible in order to reduce nephrotoxicity. After such standardized treatment, the effect of cisplatin on kidney function is very small at present. For example, fluorouracil, which is commonly used in intestinal cancer, often requires a 48-hour continuous infusion so that the drug can continue to kill tumor cells and be more effective. However, it does not require the patient to be bedridden for 48 hours. There are now portable infusion pumps that can be carried around, such as in a pocket, and daily activities are not affected.